<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
</head>
<body>

</body>
</html>
<script>
    console.log(Math.ceil(1.01))
    console.log(Math.ceil(1.9))
    console.log(Math.ceil(-1.3))
    //floor  地板   向下取整
    console.log(Math.floor(1.01))
    console.log(Math.floor(1.9))
    console.log(Math.floor(-1.3))
    // 四舍五入
    console.log(Math.round(1.01))
    console.log(Math.round(1.5))
</script>